I made some screen prints from my '79 and '84 part manuals.
1979
E44 (ELA) – 318 2-bbl
E45 (ELD) – 318 2-bbl HD (ie: Taxi or Police). These have roller timing chains and better bearings in the torque converter, but otherwise the same as E44.
E46 (ELC) – 318 4-bbl (low performance)
E47 – 318 4-bbl HD (see above, also low performance)
E53 – I've never seen one. I suspect this might be the Imperial FI for testing (maybe).
E56 - 360 4-bbl (low performance)
E57 – 360 2-bbl
E58 – 360 4-bbl High Performance
Every 318 cylinder head I have ever seen has small intake ports – with one exception (the police 318) which uses the 360 cylinder head. Now with that said, the intake manifolds are a different story (see below).
1984
ELA (E44) – 318 2-bbl
ELD (E45) – 318 2-bbl HD (ie: Taxi or Police). Again, these have roller timing chains and better bearings in the torque converter, but otherwise the same as ELA.
ELC (E46) – 318 4-bbl (low performance)
ELE – 318 4-bbl HD (see above, but this one engine is significantly different. The only parts also used on other 318's is the block and covers/pans).
The cylinder head part number for both year 318's are the same, except for the 318 4-bbl police.
The intake manifolds are the same (2 bbl vs 4 bbl) but part numbers don't reflect that. For both examples, the 4-bbl intake is the large port (360) intake. What is not shown or mentioned is the port size mismatch from large port 4-bbl intake to small port cylinder head when used on non-police engines.
Note: I thought the camshafts were different - but I was wrong (but not really looked into it before).
Chrysler did make small port 4-bbl intakes – but not a lot of them. The two years I used for examples ('79 & '84), all 4-bbl intakes, if used on 318 or 360, are the same part, but the cylinder heads NOT.
The only 318 cylinder heads, that I have ever seen (and I've seen thousands of 'em) use small intake ports – with the only exception is the police 318 4-bbl. Those engines also use radically different pistons because of the 360 head combustion chambers are made a lot differently (ie: the piston tops are closer to head gasket when at TDC.
According to the parts book, the heads, cam and possibly the intake from a 318-4V are the same as the E58 360-4V.
The camshaft and intakes I can agree with. The cylinder heads, are not (large port vs. small port).
BudW